I am looking for any help in clarifying if I am on the right track, or help to put me on the right track. There is only 1 question with my answers for now, and I would really appreciate any input.
Thank you in advance!
Also for the question I have:
-stated the null and alternative hypothesis
-stated the critical region to reject or fail to reject the null
-Identified the test stat
-found the test stat
-stated the conclusion.
A customer is in need of a large supply of copper tubing that is cut 1.25 meters long. A plumbing supply company guarantees that if you order a specified lenght, you will receive what you ordered within a standard deviation=0.0001. To test the companies guarantee, a sample of 10 pieces of the tubing was taken. The mean length of the tubing was 1.2502 meters. Assume the population is normally distributed.
a)Is there a significant difference in the specified length of the tubing at the 0.01 significance level? Based on your answer, should the customer trust the guarantee?
b)Calculate the p-value at the 0.01 significance level. Is it significant?
Ho: u=1.25 H1: u=/=1.25
Critical region: Fail to reject Ho if the test statistic falls between 2.33 and -2.33. Reject Ho if the test statistic does not fall between 2.33 and -2.33.
z=6.3 with test stat=0.0001
Conclusion: There is not sufficient sample evidence to warrant rejection of the claim that if you order a specified length of pipe, you will receive it within a standard deviation of 0.0001.
a)No, there is not a significant difference in the length of tubing at the 0.01 significance level. The customer should trust the company's guarantee.
b) P-value=0.0002 and it is not significant.